Smart Playing Cards: A Ubiquitous Computing Game

We present the ‘Smart Playing Cards’ application, a ubiquitous computing game that augments a classical card game with information technological functionality by attaching RFID tags to the cards. We also mention requirements that such an application makes on a supporting software infrastructure for ubiquitous computing. Correspondence to: Nr K. R?mer or Ms S. Domnitcheva, Department of Computer Science, ETH Zürich, 8092 Zürich, Switzerland. Email: roemer@inf.ethz.ch, or domnitch@ inf.ethz.ch     

Recent advances in brain cholesterol dynamics: Transport, domains, and Alzheimer's disease

Major advances in understanding cholesterol dynamics and the role that cholesterol plays in vascular disease have recently been made. The brain is an organ that is highly enriched in cholesterol, but progress toward understanding brain cholesterol dynamics has been relatively limited. This review examines recent contributions to the understanding of brain cholesterol dynamics, focusing on extracellular and intracellular lipid carrier proteins, membrane cholesterol domains, and emerging evidence linking an association between cholesterol dynamics and Alzheimer's disease.     

Tremorogenic effects of intracaudate d-amphetamine and their suppression by dopamine

Pronounced tremors were produced in unanesthetized cats following intracaudate (I.C.) injections of either d-amphetamine (15 mug), dl-methamphetamine (20 mug), l-amphetamine (48 mug) or 3-methoxytyramine (68-120 mug). Yet, a series of other chemically and pharmacologically related phenylethylamines, including dopamine (90 mug), were not tremorogenic even at substantially higher doses. The d-amphetamine tremors developed rapidly, failed to exhibit tachyphylaxis to repeated challenging doses (15 mug) and were not influenced by pretreatment with alpha-methyl-p-tyrosine. They also developed independently of local acetylcholine activity as evidenced by the inability of cholinergic antagonists (scopolamine and hemicholinium) to interfere with the tremors. Significant qualitative differences were found between the I.C. effects of d-amphetamine (15 mug) and dopamine (15-90 mug): d-amphetamine further increased the intensity of ongoing tremors induced by physostigmine (111 mug I.C.), whereas, dopamine readily inhibited the latter. When superimposed, I.C. dopamine was equally effective in suppressing d-amphetamine tremor activity. The results emphasize the selective tremorogenic actions of d-amphetamine and call attention to the contrasting stabilizing role of dopamine. This would suggest that two types of adrenergic receptor sites are operative in the caudate in neuroregulation of involuntary movements.     

Screening for novel essential genes of Saccharomyces cerevisiae involved in protein secretion

We describe here a screening procedure devised for searching new genes involved in protein secretion in Saccharomyces cerevisiae. The screening procedure takes advantage of yeast strains constructed within the EUROFAN project, in which the promoters of the novel essential genes were replaced by the doxycycline-regulated tetO(7)-CYC1 promoter. This promoter is active in normal growth medium but results in downregulation of the gene in the presence of doxycycline. The yeast cells were grown in the presence or absence of doxycycline, and both the growth and secretion of the heat shock protein, Hsp150p, into the culture medium were determined. In seven strains there was a specific effect on protein secretion. In a strain in which the RPN5 gene was downregulated, the level of secreted Hsp150p was increased compared to the control culture. When RER2 was downregulated, cells secreted Hsp150p that was not of the mature size. In five strains, secretion was more severely reduced than cell growth. One of these downregulated genes, YGL098w, was recently reported to encode an ER-located t-SNARE, USE1. Four of the genes detected, NOG2, NOP15, RRP40 and SDA1, encode proteins involved in ribosome assembly, suggesting a possible new signalling pathway between ribosome biogenesis and production of secreted proteins. The results obtained here indicate that the present screen could be successfully used in larger scale to identify novel secretion-related genes.     

Equating student satisfaction measures

Colleges and universities conduct student satisfaction studies for many important policy making reasons. However the differences in instrumentation and the use of students' self-reported ratings of satisfaction makes such decisions sample-, instrument-, and institution-dependent. A common metric of student satisfaction would assist decision makers by providing a richness of information not typically obtained. The present study investigated the extent to which two nationally known instruments of student satisfaction could be scaled on the same quantitative metric. Pseudo-common item equating (Fisher, 1997) based on five link items of low and high endorsability enabled comparisons of "similar, but not identical items, from different instruments, calibrated on different samples" (p. 87). Results suggest that both instruments measured similar constructs and could be reasonably used to create a single, common metric. While samples used in the experiment were less than ideal, results clearly demonstrated the usefulness and reasonability of the pseudo-common item equating process.     

Mechanical characteristics of optical coatings prepared by various techniques: a comparative study

Good performance of optical coatings depends on the appropriate combination of optical and mechanical properties. Therefore, successful applications require good understanding of the relationship between optical microstructural and mechanical characteristics and film stability. In addition, there is a lack of standard mechanical tests that allow one to compare film properties measured in different laboratories. We give an overview of the methodology of mechanical measurements suitable for optical coatings; this includes depth-sensing indentation, scratch resistance, friction, abrasion and wear testing, and stress and adhesion evaluation. We used the techniques mentioned above in the same laboratory to systematically compare the mechanical behavior of frequently used high- and low-index materials, namely, TiO2, Ta2O5, and SiO2, prepared by different complementary techniques. They include ion-beam-assisted deposition by electron-beam evaporation, magnetron sputtering, dual-ion-beam sputtering, plasma-enhanced chemical-vapor deposition, and filtered cathodic arc deposition. The mechanical properties are correlated with the film microstructure that is inherently related to energetic conditions during film growth.     

Impact of Fiber Non-linearity in High Capacity WDM Systems and in Cross-Connected Backbone Networks

The rapidly increasing data traffic volumes will demand for very high transmission capacity and network nodes throughput. Wavelength division multiplexing (WDM) technology will be asked to support many channels on the same fiber, both in point-to-point links and in WDM optical networks. The transmission of a high number of wavelength channels in all these systems is a key issue. This paper analyzes this topic, in both high capacity links and optical networks, highlighting the impact of fiber non-linearity, and addressing the main source of impairments. This is done through the use of a semi-analytical model recently upgraded to account for all the contributions deriving from Kerr effects, particularly four-wave mixing and cross-phase modulation. The analysis reveals that more than one hundred of channels at 2.5 Gbit/s can be transmitted in point-to-point links whose length can span until the order of 1000 km, and 32 channels per fiber, at the previous bit rate, can be handled in WDM networks, without dispersion compensation. For a higher number of channels (e.g., 64) dispersion compensation is needed.     

The complexity of mean flow time scheduling problems with release times

We study the problem of preemptive scheduling of n} jobs with given release times on m identical parallel machines. The objective is to minimize the average flow time. In this paper, show that when all jobs have equal processing times then the problem can be solved in polynomial time using linear programming. Our algorithm can also be applied to the open-shop problem with release times and unit processing times. For the general case (when processing times are arbitrary), we show that the problem is unary NP-hard. P. Baptiste and C. Dürr: Supported by the NSF/CNRS grant 17171 and ANR/Alpage. P. Brucker: Supported by INTAS Project 00-217 and by DAAD PROCOPE Project D/0427360. M. Chrobak: Supported by NSF grants CCR-0208856 and INT-0340752. S. A. Kravchenko: Supported by the Alexander von Humboldt Foundation.     

An Adaptive Differentiation Filter for Tracking Instantaneous Frequency in Power Systems

This paper presents an application of adaptive differentiation filter in tracking instantaneous frequency in electrical power systems. For each new sample, the filter automatically selects an optimal window length that maximizes measurement accuracy. Large window length is selected if the frequency is slow varying or steady state, to increase efficiency in filtering noise and harmonics. For fast-varying frequency, the window length is automatically reduced in order to make frequency tracking more accurate, sacrificing filtering efficiency. Automatic selection of the optimal window length that balances between tracking and filtering performance is the unique feature of this technique. This paper concludes with the presentation of the representative results obtained in the simulation study as well as in some practical applications. The results show the adaptive differentiation filter gives accurate frequency measurement under both steady-state and dynamic conditions     

The use of natural Kazakhstan zeolites for the development of gas purification catalysts

The results of investigation of catalysts based on natural zeolite in comparison with synthetic ZSM-5 zeolite used in reduction of nitrogen oxides and conversion of carbon monoxide are presented. It was found that rearrangement of the crystal structure of natural zeolite begins upon heating it above 500 °C in air. The structure of natural zeolite has been improved by introduction of various modifiers and selection of thermal regime of samples training. It has been shown that developed compositions of press-mass for preparation of carriers for gas purification catalysts in the form of granules and tablets satisfy the requirements on ductility and mechanical strength. The efficiency of synthesized granular and block Cu–Ce, Cu–Ni–Cr, Ti–V, Ti–VW, and TiO₂–V₂O₅ catalysts based on natural and synthetic zeolites was determined in conversion of CO and nitrogen oxides. The results of X-ray structure analysis of clinoptilolite of the Republic of Kazakhstan deposits—Chankanai and Taizhuzgen—are represented in comparison with synthetic ZSM-5 zeolite. The paper also comprises data about their thermal stability, ductility, and strength of compositions on their base. Metals particles morphology and dispersity are studied by the method of electronic microscopy. These particles were used as active components of synthesized catalysts.